1. Field of Invention
The present invention relates to a light emitting device.
2. Description of Related Art
As the technology advances, lower power and high-efficiency light emitting devices are more desired by modern persons. Therefore, LED (light emitting diode) lamps would gradually replace the conventional light emitting devices.
The LED is a semiconductor device, which is equipped with several advantages, such as high-efficiency, rapid response time and mercury-free. Besides, LED is also equipped with advantages of small volume, enduring higher mechanical impact and broad color gamut. As the white LED technology has been well developed, various LED applications on general illumination purpose are being performed and the LED seems the promising illumination device in the 21st century.
However, a conventional LED lamp is only equipped with an emitting angle range of about 120 degrees, i.e. 60 degrees left or right from a normal line of an emitting surface. Compared with a conventional non-LED lamp, the emitting angle range of the LED lamp seems narrower, thereby preventing the LED lamp from broadly uses on general illumination purpose.